Network+ Midterm

What are the basic troubleshooting steps?

1. Identify problem 2. Establish theory of probable cause 3. Test theory to determine cause 4. If theory proved, establish action plan 5. Implement solution or escalate 6. Verify full functionality 7. Document Findings, actions, and outcomes

802.11b

11 Mbps

MTU Standard

1500

How many bits of a Class B IP address is used for host information?

16 bits = 8 bits + 8 bits

How tall are half racks?

18U-22U Tall

What are the basic dimensions of a rack or cabinet?

19 in wide (sometimes 23 in wide) and 42U Tall (about 6 ft)

802.11a

54 Mbps

801.11g

54 Mbps - compatible with and replaced 802.11b, and has been superseded by the 802.11n standard.

IPSec (Internet Protocol Security)

A Layer 3 protocol that defines encryption, authentication, and key management for TCP/IP transmissions. IPSec is an enhancement to IPv4 and is native to IPv6. IPSec is unique among authentication methods in that it adds security information to the header of all IP packets.

MAC Address

A Media Access Control address is a hardware address that uniquely identifies each node on a network. (48 bits, hexadecimal, first half is the OUI-organizationally unique Identifier and the second half is the device ID)

ifconfig

A command-line tool used on Linux systems to show and manipulate settings on a network interface card (NIC). Similar to ipconfig used on Windows systems. - Displays only active connections

IPv4 Addressing

A connectionless protocol used on Ethernet networks. IPv4 is a unique identifier for a computer or device.

Second-Level Domain

A domain that falls within top-level domains of the Internet. Each second-level domain needs to be unique within that particular domain but not necessarily unique to all top-level domains. (amazon, google, yahoo, etc.)

Multimode Fiber (MMF)

A fiber optic cable used to transmit multiple signals at the same time. It cannot transmit signals as far as SMF can.

Site-to-Site

A type of VPN connection that uses two concentrators, placed in separate locations. All of the hosts in each location go through their own respective VPN concentrator to contact the distant-end VPN concentrator, thus allowing them access into the other network.

Client-to-Site

A type of VPN connection where a single computer logs into a remote network and becomes, for all intents and purposes, a member of that network.

SMF (single-mode fiber)

A type of fiber-optic cable with a narrow core that carries light pulses along a single path data from one end of the cable to the other end. Data can be transmitted faster and for longer distances. However, it is expensive.

Link-state

A type of routing protocol that enables routers across a network to share information, after which each router can independently map the network and determine the best path between itself and a packet's destination node.

MIMO

"Multiple Input/Multiple Output," or "MIMO," which enables the devices to make multiple simultaneous connections called "streams." With up to 4 antennas, 802.11n devices can achieve amazing speeds.

WPA2-PSK

"WPA2-PSK" is "Pre-Shared Key" mode, also called "Personal" mode. In this mode, you add a secret key to all devices on the same SSID.

SMTP

(Simple Mail Transfer Protocol) The main protocol used to send electronic mail from server to server on the Internet.

Device that marks where the service provider's network ends and the private network begins

Demarcation Point (Demarc)

What makes a WAN harder to discover?

Disabling SSID broadcast:

DNS Architecture

Distributed

DNS

Domain Name System - The service that translates URLs to IP addresses.

ESD

Electrostatic Discharge

XaaS (Anything as a Service)

Expressing the concept that most types of IT requirements can be deployed as a cloud service model.

EGP

Exterior Gateway Protocol; protocol for communication between Autonomous Systems.

True or False: A /14 CIDR block is equivalent to a 255.255.255.0 subnet mask?

False

True or False: A dynamically allocated virtual hard disk file will grow and shrink to meet the needs of the virtual machine.

False

True or False: An unmanaged switch can still support the creation of VLANs, provided there is an interface for configuration.

False

True or False: Telnet protocol does both authentication and encryption. Telnet encrypts data exchanged throughout the session.

False

True or False: The HTTPS (HTTP Secure) protocol utilizes the same TCP port as HTTP, port 80.

False

True or False: WPS (Wi-Fi Protected Setup) attacks involve an interception of the network keys communicated between clients and access points.

False

FTP

File Transfer Protocol

wireless spectrum

Frequencies used for communication. Most mobile cell phone services have to license spectrum. Some technologies (such as Wi-Fi) use unlicensed public spectrum.

FQDN

Fully Qualified Domain Name - consists of a host ID and domain name (e.g., www.amazon.com)

A lightweight protocol used to carry error messages and information about a network.

ICMP (Internet Control Message Protocol)

An address assigned to each node on a network

IP Address

IPv6 Link Local

IPv6 version of APIPA. Automatically configured, and only usable on local segment. (fe80::/64)

In a DNS zone, what type of record holds the name-to-address mapping for IPv6 addresses?

AAAA Record

Can sign on from any computer

ADDS (Active Directory Domain Services)

An IPv6 link-local address is an equivalent of IPv4's:

APIPA address

Works in conjunction with IPv4 to discover the MAC address of a node on the local network and to maintain a database that maps local IP addresses to MAC addresses.

ARP (Address Resolution Protocol)

AD

Active Directory - centralized directory database, contains user and other resources info

ADDS

Active Directory Domain Services

AAA

Authentication, Access Control, Auditing

The only routing protocol that communicates across the internet

BGP (Border Gateway Protocol)

What is by far the most popular DNS server software available?

BIND

Central conduit connecting multiple network segments

Backbone

Consists of links that provide interconnection between the entrance facility and the MDF and horizontal and verticle cabling going from the MDF to IDF(s)

Backbone

Multipath signals

Because of reflection, diffraction, and scattering, wireless signals follow a number of different paths to their destination.

BGP

Border Gateway Protocol

Type 1 Hypervisor

Also known as a bare metal hypervisor it is a software program that acts as an operating system and also provides the ability to perform virtualization of other operating systems using the same computer.

Loopback Address

An IP address that indicates your own computer and is used to test TCP/IP configuration on the computer.

Public Address

An IP address that is valid for use on public networks, such as the Internet. An organization assigns its hosts public addresses from the range of addresses assigned to it by Internet numbering authorities. (A, B, C, etc.)

Private Address

An IP address used only on an organization's internal network. Certain IP address ranges are reserved for private addresses. Private addresses cannot be used to communicate over the Internet.

Dual Stack

An IPv4-to-IPv6 transition method that runs both IPv4 and IPv6 on networking devices.

Symmetric Encryption

An encryption method whereby the same key is used to encode and to decode the message

CAN

Campus Area Network

In IPv4 addressing, the leading octet of an IP address with a value of 1 through 126 denotes that the IP address within that range belongs to the:

Class A address space

CTS

Clear to Send

POP3

Post Office Protocol 3

Methods and rules for communication

Protocols

PKI

Public Key Infrastructure- Developed to provide standards for key generation; authentication; x.509 non used with Pretty Good Privacy; good private good "web of trust"

A vSwitch (virtual switch) or bridge is a logically defined device that operates at what layer of the OSI model?

Layer 2 - Data Link Layer

LAN

Local Area Network; a geographic network that covers a relatively small geographic area such as a building or a small campus - no more than a mile distance between computers

Describes how access to the network is controlled/software

Logical Topology

What is an essential part of network documentation?

Logical and physical connections on a network

Broadcast Domain

Logically grouped network nodes that can communicate directly via broadcast transmissions. By default, switches and repeating devices, such as hubs, extend broadcast domains. Routers and other Layer 3 devices separate broadcast domains. Data Link Layer

MLA

Master License Agreement - grants a license from a creator, developer, or producer, such as a software producer, to a third party for the pur- poses of marketing, sublicensing, or distributing the product to consumers as a stand-alone product or as part of another product.

MSA

Master Service Agreement - a contract that defines the terms of future contracts between parties, such as payment terms or arbitration arrangements.

MTU

Maximum Transmission Unit. The MTU identifies the size of data that can be transferred.

MTBF

Mean Time Between Failure: a measure of availability often quoted by hardware manufacturers. For example 2.56 years between failures means that, on average, the hardware can be expected to last 2.56 years before it goes wrong.

MTTR

Mean Time to Recover or Mean Time to Repair

Speed Metric

Measures the ability of a computer to complete a single task

MOU

Memorandum of Understanding - documents the intentions of two or more parties to enter into a binding agreement, or contract, and is sometimes used between an informal handshake and the legally binding signatures on contracts.

MAN

Metropolitan Area Network; a geographic network that covers a larger geographic area such as a city or community; may be used to connect computers in libraries, government agencies, etc. together - no more than 30 miles in size

A relatively short cable with connectors on both ends.

Patch Cable

Panel of data receptors that can be mounted to a wall or rack

Patch Panel

P2P Network Model

Peer-to-Peer - · no centralized control - each computer controls access to its resources

Drawing that shows devices stacked in a rack system

Rack Diagram

RFID

Radio Frequency Identification

TCP Sequencing and Acknowledgement

Receiver sends an acknowledgement number which is equal to the senders sequence number + the number of bytes of data + 1

PAN

Personal Area Network - smallest network

SSH

Secure Shell Port 22 Enables a session to be open on a remote host. Differs from Telnet because it provides additional authentication methods and encryption for data as it traverses the network.

SSL

Secure Sockets Layer. The predecessor to TLS. SSL is used to encrypt data-in-transit with the use of certificates.

SMB

Server Message Block Port 445 Port 137-139

SLA

Service Level Agreement - is a legally binding contract or part of a contract that defines, in plain language and in measurable terms, the aspects of a service provided to a customer, such as the service provided by an ISP.

SaaS (Software as a Service)

Services for delivering and providing access to software remotely as a web-based service

Hypervisor

Software that creates and manages virtual machines on a server or on a local computer. Also called virtual machine manager (VMM).

A computer networking device that connects network segments

Switch - only belongs to it's local network

SLC

System Life Cycle

Connection Oriented Protocol

TCP (Transmission Control Protocol)

SSH

TCP 22

TelNet

TCP 23

Suite of protocols used by operating systems for communication

TCP/IP

Which protocol used on the Internet gives each computer a unique address?

TCP/IP

In the event of a duplicate MAC address shared by two hosts on a switched network, what statement is accurate?

The hosts will still send and receive traffic, but traffic may not always reach the correct destination.

One of your coworkers downloaded several, very large video files for a special project she's working on for a new client. When you run your network monitor later this afternoon, what list will your coworker's computer likely show up on?

Top Listeners

How parts of a network work together

Topology

TCP

Transmission Control Protocol

The TCP and UDP protocols both exist at what layer of the OSI model?

Transport

TLS

Transport Layer Security. Used to encrypt traffic on the wire. TLS is the replacement for SSL and like SSL, it uses certificates issued by CAs.

True or False: 802.11ac access points function more like a hub than a switch.

True

True or False: Fibre Channel (FC) is a storage networking architecture that runs separately from Ethernet networks to maximize speed of data storage and access.

True

True or False: Network segmentation at Layer 2 of the OSI model is accomplished using VLANs.

True

True or False: The most secure Wi-Fi communication is made possible by combining a RADIUS server with WPA or WPA2, known as WPA-Enterprise or WPA2-Enterprise, respectively.

True

What is the difference between Active Directory vs. Work Group/Peer-to-Peer?

The first is a centralized database, and the other doesn't allow computers to talk to each other.

IPv6 Prefix

The first numbers in an IPv6 address that identify the type of IPv6 address. For example, it can be a global unicast address (prefix of 2), a link-local address (prefix of fe80), a unique local address (prefix of fd), or a Teredo address (prefix of 2001:000).

Based on the kinds of endpoints VPNs connect, which one of the following is not a model of VPN. site-to-site VPN host-to-client VPN client-to-site VPN host-to-host VPN

host-to-client

Distance Vector

measures hops between nodes based on local updates from all your neighbors

Public Cloud

promotes massive, global, and industrywide applications offered to the general public

TCP Flow Control

receiver controls sender, so sender won't overflow receiver's buffer by transmitting too much, too fast

VLAN Segmentation

reduces size and increases number of broadcast domains

client server network model

resources managed by centralized directory database

801.11ac Wave 2

3.47 Gbps

Decimal numbering system

0-9

TCP Connection Establishment

1. Initiating client requests a client-to-server communication session with the server 2. The server acknowledges the client-to-server communication session and requests a server-to-client communication session 3. The initiating client acknowledges the server-to-client communication sessions 1.SYN 2.SYN ACK 3.ACK

802.11ac Wave 1

1.3 Gbps

How many volts of ESD does it take to damage a component?

10 volts

What is the maximum length an ethernet cable should be?

100 M

801.11n

600 Mbps, 2.4 and 5 GHz

IPv4 Hop Limit

64

IPv6 Hop Limit

8 Bits

802.11ax

9.6 Gbps (Note* Has not yet been added to the CompTIA A+ objectives.... but it's really cool.)

MTU Jumbo

9000 or more

TCP Checksum

9th Field of TCP Header

IPv4 Mask

A 32-bit series with a number of 1s followed by the number of 0s. The number of 1s corresponds either to the IKPv4 packet's network part or network plus subnet part. Used by routers to assign routes to all packets going to a particular network or subnet on a network.

Relay Agent

A networking device (such as a router or firewall) configured to support UDP forwarding.

Hexadecimal Number System

A number system consisting of 16 distinct symbols — 0-9 and A-F — which can occur in each place value.

IaaS (Infrastructure as a Service)

A service model in which hardware services are provided virtually, including network infrastructure devices such as virtual servers.

PaaS (Platform as a Service)

A service model in which various platforms are provided virtually, enabling developers to build and test applications within virtual, online environments tailored to the specific needs of a project.

Type 2 Hypervisor

A software program that sits on top of an existing operating system and provides the ability to host multiple virtual operating systems on the same computer at the same time.

Cloud Computing

A system in which all computer programs and data is stored on a central server owned by a company (e.g. Google) and accessed virtually

MAC address table

A table of forwarding information held by a Layer 2 switch, built dynamically by listening to incoming frames and used by the switch to match frames to make decisions about where to forward the frame.

Captive Portal

A technical solution that forces wireless clients using web browsers to complete a process before accessing a network. It is often used to ensure users agree to an acceptable use policy or pay for access.

ARP

Address Resolution Protocol

How are devices connected in a Star topology?

All devices connect to one central device

How are devices connected in a Bus topology?

All devices in the network are connected by one central line

What is the most popular web server application?

Apache

API

Application Programming Interface; a code library for building programs

How do computers communicate with each other?

By protocols they have in common

CA

Certificate Authority. An organization that manages, issues, and signs certificates and is part of a PKI. Certificates are an important part of asymmetric encryption. Certificates include public keys along with details on the owner of the certificate and on the CA that issued the certificate. Certificate owners share their public key by sharing a copy of their certificate.

Zones

Chunks

The grouping of multiple servers so that they appear as a single device to the rest of the network is known as which term?

Clustering

Virtualization

Creates multiple "virtual" machines on a single computing device

While designing your network's VLAN topology, your team has decided to use a centrally managed DHCP server rather than creating a separate DHCP server for each VLAN. What software/service/configuration will you need in order to make the central DHCP server accessible across VLANs?

DHCP relay agent

Collisions

Data collisions happen when two or more computers try to send data across the same cable. This cancels the data, which must be sent again. This can greatly slow down a network. Star and Mesh networks are the least likely to have data collisions.

Encryption and Key Management

Encrypts data and manages encryption keys. Includes proxies that encrypt sensitive data.

Term for incoming network

Entrance Facility - such as the internet

Wi-Fi Analyzer

Hardware and/or software that monitors a Wi-Fi network to detect devices not authorized to use the network, identify attempts to hack transmissions, or detect performance and security vulnerabilities.

WPA2-Enterprise

Has all the features of WPA2 but allows for the use of RADIUS servers (AAA - Authentication, Access Control, Auditing)

Connects workstations to the closest data room.

Horizontal Cabling

Any computer on a network that hosts a resource such as an application or data

Host

What is a topology that combines different topologies?

Hybrid Topology - Star-Bus topology

HTTP

HyperText Transfer Protocol - the protocol used for transmitting web pages over the Internet

HTTPS

Hypertext Transfer Protocol Secure - Encrypts HTTP traffic with SSL or TLS using port 443.

Name two common hardware changes

Installing new hardware Upgrading current hardware example: replacing network backbone

IGP

Interior Gateway Protocol. Identifies the protocols used to exchange routing information between routers within LAN or interconnected LAN's.

IDF

Intermediate Distribution Frame - often called data room or closet

ICMP

Internet Control Message Protocol

IIS

Internet Information Services. A Microsoft Windows web server. IIS comes free with Microsoft Windows Server products.

IMAP4

Internet Message Access Protocol v4

ISP

Internet Service Provider - A company that provides access to the Internet.

iSCSI

Internet Small Computer System Interface. A lower-cost alternative to traditional SANs. It supports sending traditional SCSI commands over an IP network.

A network TAP serves what purpose on a network?

It monitors network traffic at a specific point in the network.

MDF

Main Distribution Frame - · centralized point of interconnection for the LAN and WAN

MU-MIMO

Multi-User Multiple Input/Multiple Output. Allows multiple users to access the wireless network and access point at the same time.

NAS

NAS (network attached storage) A specialized storage device or group of storage devices that provides centralized fault-tolerant data storage for a network.

System where computers (clients) don't share their resources directly with each other. Clients access resources by servers controlling domain database (client network model)

NOSes (Network Operating Systems)

A group of computers that are connected by some type of transmission media

Network

NFS

Network File System. Access files across the network as if they were local.

NIC

Network Interface Card

NOS

Network Operating System - Controls access to the network

NOSes

Network Operating Systems

Any computer or device on a network that can be addressed on the local network

Node - routers and switches don't host, they are just nodes

Each managed device on the network contains several managed objects, which are any characteristics of the device that is monitored, including components such as a processor, memory, hard disk or NIC, or intangibles such as performance. What is the managed object's assigned name?

Object Identifier (OID)

o How devices and cables fit together to form the physical network

Physical Topology

The number the transport layer header addresses the receiving application by.

Port

RDP

Remote Desktop Protocol

RFB

Remote Frame Buffer - A protocol used in VNC for remote access and graphical user interfaces (GUis).

RFP

Request for Proposal - document that stipulates what services the organization wants from an outside contractor and requests a bid to perform such services

RTS

Request to Send

A device that manages traffic between two or more networks and can help find the best path for traffic to get from one network to another

Router

What device is a gateway between two networks

Router - belongs to 2 or more networks

SAN

SAN (storage area network) A distinct network of storage devices that communicate directly with each other and with other networks.

What is the process of designing, implementing , and maintaining an entire network?

SLC (system life cycle)

STP

Shielded twisted pair. Cable type used in networks that includes shielding to prevent interference from EMI and RFI. It can also prevent data from emanating outside the cable.

The main protocol used to send electronic mail from server to server on the Internet.

Simple Mail Transfer Protocol

SNMP

Simple Network Management Protocol

SOHO

Small Office Home Office. A term used to define the general working environment of small businesses and home based businesses.

Structured Cabling

Standards defined by TIA/EIA that define methods of organizing the cables in a network for ease of repair and replacement.

SOW

Statement of Work - documents in detail the work that must be completed for a particular project, and includes specifics such as tasks, deliverables, standards, payment schedule, and work timeline.

AAAA record

The DNS record that maps a hostname to a 128-bit IPv6 address.

IPv6 neighbor table

The IPv6 equivalent of the ARP table. A table that lists IPv6 addresses of other hosts on the same link, along with their matching MAC addresses, as typically learned using Neighbor Discovery Protocol (NDP).

You have been tasked with maintaining a network that is jumbo frame enabled. What does this mean?

The MTU for the network can be as high as 9198 bytes.

OUI (Organizationally Unique Identifier)

The Organizationally Unique Identifier is the first half of the MAC address, designating the manufacturer of the network device. Each manufacturer has their own individual OUI for each device they produce.

Binary

The binary number system is base 2, using only bits 0 and 1.

What is the difference between Server vs. Client/Workstation?

The first is a centralized database for storing information and the other is a workstation or computer connected to the network

Diffraction has what affect on a wireless signal's propagation?

The signal is split into secondary waves that continue in the direction in which they split.

Root Domain

The uppermost domain in a domain tree and the root of the domain hierarchical structure.

ipconfig

The utility used to display TCP/IP addressing and domain name information in the Windows client operating systems. · Displays all current TCP/IP network configuration values

netstat command

This displays TCP and UDP connections.

TTL

Time to Live - A value that determines how many hops an IP packet can travel before being discarded.

Host-to-Host

Type of VPN connection in which a single host establishes a link with a remote, single host.

Connectionless protocol

UDP (User Datagram Protocol)

UNC

Universal Naming Convention

UTP

Unshielded Twisted Pair. Cable type used in networks that do not have any concerns over EMI, RFI, or cross-talk. If these are a concern, STP is used.

UDP

User Datagram Protocol

VNC

Virtual Network Computing (VNC) operates much like RDP but uses the Remote Frame Buffer (RFB) protocol. Unlike RDP, VNC is platform independent.

VLAN

Virtual local area network. A VLAN can logically group several different computers together, or logically separate computers, without regard to their physical location. It is possible to create multiple VLANs with a single switch.

VoIP

Voice over Internet protocol - a phone connection through a personal computer with any type of broadband Internet connection.

2.4 GHz and 5 GHz

What are the most common frequencies used on Wi-Fi networks?

802.11ac Wave 3

Wi-Fi 5 -6.93 Gbps

WAN

Wide Area Network; largest type of network in terms of geographic area; largest WAN is the Internet

WFS

Windows File Sharing

WEP

Wired Equivalence Protocol. Wireless network encryption system.

WLANs

Wireless Local Area Networks. Networks that transmit signals through the air via radio frequency (RF) waves Wired and wireless signals share many similarities Use of the same Layer 3 and higher protocols The nature of the atmosphere makes wireless transmission different from wired transmission

WPA

Wireless Protected Access

WPA2

Wireless Protected Access 2. Wireless network encryption system.

Graphical representation of network's wired infrastructure

Wiring Schematic - In detailed form shows every wire interconnecting network devices

Asymmetric Encryption

a type of cryptographic based on algorithms that require two keys -- one of which is secret (or private) and one of which is public (freely known to others).

ping

a DOS command that tests connectivity and isolates hardware problems and any mismatched configurations

Diffraction

a change in the direction of a wave when the wave finds an obstacle or an edge, such as an opening

Database

a collection of organized data that allows access, retrieval, and use of data

Digital Certificate

a notice that guarantees a user or a website is legitimate

Ethernet

a physical and data layer technology for LAN networking

What kind of packet is sent from the server to the client to indicate the completion of the four-packet DHCP Discovery process?

acknowledgement

overlapping channels

are also called adjacent channels, providing channel interference

What is NOT one of the three characteristics of TCP in its role as a reliable delivery protocol?

framing

Top-level Domain

last portion of a web name; includes examples such as ".com", ".org" or ".net"

Windows Domain

logical group of computers a Windows Server controls

Why should you have up-to-date and detailed documentation of your network?

o More efficient communication o Speeds up troubleshooting o Puts info at fingertips when facing similar future problems

What are the common change management principles?

o Process through proper channels o Minimize negative impacts on business procedures o Plan to thoroughly to maximize chance of successful change o Document each change throughout the process

Name four common software changes/updates

patches - correction, improvement, or enhancement upgrades - major change that enhances functionality rollbacks - backleveling or downgrading - reverting to a previous version installation - new software

What Windows utility uses ICMP echo requests to trace the path from one network node to another, identifying all intermediate hops between the two nodes?

ping

Private Cloud

serves only one customer or organization and can be located on the customer's premises or off the customer's premises

What are two benefits of inventory management?

· Simplifies maintaining and upgrading a network · Provides info about costs of hardware and software